The present invention relates to cross-connect systems and, in particular, to a system having a chassis and a mount apparatus.
A digital cross-connect system (DSX) provides a location for interconnecting two digital transmission paths. DSX is generally located in one or more frames or bays in a central office, e.g. a central telephone office. DSX also provides jack access to the transmission paths.
DSX jacks are known in the art to provide spring contacts for receiving tip and ring plugs. The jacks are commonly ganged in a common housing that is mounted on a frame. The jacks are typically hard wired to wire termination pins or other connection locations that are mounted on a side of the housing opposite plug access openings.
Recent DSX systems include U.S. Pat. No. 4,840,568 (the ""568 patent) and U.S. Pat. No. 5,393,249 (the ""249 patent), commonly assigned to ADC Telecommunications, Inc., and are incorporated herein by reference. In assembling a DSX system as in the ""568 patent, an operator typically uses a wire wrap gun to drive a wire or cable onto a wire wrap pin that extends from a back side of the mount. The opposite end of the wire wrap pin is a spring contact for contacting an electrical contact of a jack circuit board. During assembly, it might be possible for the operator to apply excessive force in driving the wire or cable onto a wire wrap pin/spring contact. The excessive force tends to push the wire wrap pin/spring contact out of a retention position on the mount.
U.S. Pat. No. 5,374,204 (the ""204 patent) describes an electrical terminal with a compliant pin section. This patent describes transition sections that resist movement of the pin leg sections toward each other. This movement generates an outwardly directed spring force normal to the planes of the leg sections. In other words, the pin leg sections are designed to have a gap therebetween and the transition sections are designed to keep the gap between the pin leg sections thus creating a spring force. This type of a compliant pin has disadvantageous. One such disadvantage is that the creation of a spring force as described can weaken the spring force exerted at an opposite end of the compliant pin.
Therefore, improvements are desired.
One aspect of the present disclosure relates to a mount apparatus having a separate spring contact and wire wrap pin assembly as well as having a multi-layer or sandwich construction to prevent the spring contact and wire wrap pin from being pushed out of their retention positions.
In one embodiment of the present disclosure, a mount apparatus includes a front cover having a plurality of receptacles, a back cover having a plurality of through holes, and a circuit board assembly sandwiched between the front cover and the back cover. The circuit board assembly includes a board having a plurality of through holes aligned with the receptacles of the front cover and the through holes of the back cover, a plurality of contacts retained in a first set of the through holes of the board of the circuit board assembly, and a plurality of pins retained in a second set of the through holes of the board of the circuit board assembly. A first end of each contact is extended towards and exposed in a corresponding receptacle of the front cover and stopped by the front cover, and a second end of each contact is extended towards and stopped by the back cover. A first end of each pin is extended towards and stopped by the front cover, and a second end of each pin is extended towards and projected from a corresponding through hole of the back cover. Further, the circuit board assembly includes a trace electrically connecting each contact to each corresponding pin.
Another aspect of the present disclosure relates to a jack assembly for a cross-connect system, for example a DSX system, which not only incorporates electronic component surface mount technology into the jack assembly, but also permits an operator to perform desired cross-connect wiring without need to access a rear portion of the system.
In one example embodiment of the present disclosure, the jack assembly includes a jack circuit board having a plurality of electrical contacts at one side, a plurality of electrical wires, a jack mount for mounting the jack circuit board and electrically cross-connecting the electrical contacts of the jack circuit board to the electrical wires. The jack mount includes a front cover having a plurality of receptacles, a back cover having a plurality of through holes, a circuit board assembly sandwiched between the front cover and the back cover. The circuit board assembly includes a board having a plurality of through holes aligned with the receptacles of the front cover and the through holes of the back cover, a plurality of contacts retained in a first set of the through holes of the board of the circuit board assembly, and a plurality of pins retained in a second set of the through holes of the board of the circuit board assembly. A first end of each contact is extended towards and exposed in a corresponding receptacle of the front cover and stopped by the front cover, and a second end of each contact is extended towards and stopped by the back cover. A first end of each pin is extended towards and stopped by the front cover, and a second end of each pin is extended towards and projected from a corresponding through hole of the back cover. Further, the circuit board assembly includes a trace electrically connecting each contact to each corresponding pin. The electrical contacts of the jack circuit board are electrically connected to the contacts of the circuit board assembly of the jack mount. Accordingly, the electrical wires are electrically connected to the pins of the circuit board assembly of the jack mount.
In addition to many other advantages, the present disclosure provides a more robust mount apparatus for a jack assembly in a cross-connect system.
A further aspect of the present disclosure relates to a method of cross-connect wiring a first cable to a second cable. In one embodiment, the method includes the step of providing a jack circuit board having an electrical contact at a first side and a termination pin at a second side, the first cable being coupled to the termination pin at the second side of the jack circuit board, the step of providing a mount having a front cover, a back cover, and a circuit board assembly sandwiched between the front and back covers, the front cover, back cover, and circuit board assembly being configured and arranged to retain a spring contact and a wire wrap pin on the circuit board assembly, the spring contact and the wire wrap pin being physically separate from each other and electrically in contact via a trace disposed on the circuit board assembly, the step of wiring the second cable onto the wire wrap pin which extends from a back side of the mount, and the step of sliding the first side of the jack circuit board onto the front cover of the mount wherein the electrical contact of the jack circuit board is coupled to the spring contact of the circuit board assembly of the mount.
The method further includes the step of replacing the jack circuit board with a second jack circuit board, the second jack circuit board having an electrical contact at a first side and a termination pin at a second side, a third cable being coupled to the termination pin at the second side of the second jack circuit board. The replacing step includes the step of pulling the jack circuit board out of the mount, and the step of sliding the first side of the second jack circuit board onto the front cover of the mount wherein the electrical contact of the second jack circuit board is coupled to the spring contact of the circuit board assembly of the mount, whereby cross-connect wiring between the second and third cables can be performed without need for access to the back side of the mount.
Another aspect of the present disclosure includes an electrical terminal adapted for insertion into a through hole of a circuit board. The electrical terminal includes a first section, a second section, and a third section. The first section receives an electrical contact and has first and second spring arms proximate to each other at a contact point and are configured to exert a spring force to retain the electrical contact. The second section is adapted for insertion into the through hole of the circuit board. The second section has first and second pin members proximate to each other. The first and second pin sections define slots configured to exert a spring force to retain the electrical terminal in the through hole of the circuit board. The third section is integral with the first and second sections. The third section has a plurality of stop members configured to prevent the electrical terminal from being pushed through the through hole of the circuit board.
Another aspect of the present disclosure includes a system. The system includes a frame and a mount apparatus. The mount apparatus includes features previously described.
Another aspect of the present disclosure includes a system having a chassis and at least one mount apparatus mounted in the chassis. The chassis is arranged and configured to retain a plurality of mount apparatuses. The chassis includes a power bus having a plurality of power plugs for providing electrical power. The mount apparatus includes a power receptacle for receiving electrical power from one of the plurality of power plugs.
Another aspect of the present disclosure includes a system having a chassis arranged and configured to retain a plurality of mount apparatuses. The mount apparatuses includes a front cover having a plurality of receptacles, a back cover having a plurality of through holes, and a circuit board assembly sandwiched between the front cover and the back cover.